Sun Safety for your Skin

The science of protecting your skin from the harsh rays of the sun is far from perfect. Until the rise of beach culture in the mid-20th century, the preoccupation among a certain class of people was to keep themselves as pale and protected from the scourge of sun-kissed skin as possible, lest they be thought to have spent time working the fields.

Growers, of course, spend hours every day of the outdoor season in the fields tending to their crops. So how do you walk the fine line between toasted god and boiled lobster? It’s a fact that covering up is the only sure-fire way to stave off a burn. As for sun protection products? It’s complicated, but with the array of options available, there’s no excuse to get burned.

The sun’s UVA and UVB rays both damage the skin, but while UVB rays damage the outer layers, causing painful sunburns, UVA rays are the worst offenders, penetrating the deeper layers of skin and re-emerging decades later as cancers and premature wrinkles.

Here’s where sun protection gets tricky: Sunscreens contain a number of tried-and-true organic molecules that absorb the sun’s ultraviolet radiation, releasing it as heat, but regardless of the skin protection factor (SPF), a sunscreen will only protect from UVB rays. UVA rays, meanwhile, require sunblock containing zinc oxide, avobenzone or titanium dioxide. Sunblock is generally thicker and less able to absorb into the skin—think of those white-streaked tourists you see on the beach.

When it comes to deciding on SPF, the formula is subjective, based on the level of melatonin in your skin. If you can stay in direct sunlight for 15 minutes before burning, an SPF 20 will offer 300 minutes (or five hours) of relative protection. By the same calculation (time before burning multiplied by SPF), an SPF 30 sunscreen will get you seven and a half hours, assuming you don’t sweat it off in that time.

The general consensus among dermatologists is that higher SPF is always better, but no sunscreen offers 100% protection from the sun’s damage. And above SPF 45, the difference in protection offered is so little as to be negligible.